.navbar {
    margin-bottom: 0px;
}
#abc{width: 50%;}
#carousel-example-generic{height: 500;margin-top: 50px;}
.top_class{margin: 30px 0;}
.top_class h3,.case h3{text-align: center;margin-bottom: 20px;}
.t_b_list img{width: 90px;height: 90px;margin: 0 auto;display: block;}
.top_class h4,.case_list h4{text-align: center;color: #333;font-size: 18px;}

.case_list img{width: 220px;height: 200px;}